Both websites are primarily concerned with the history of long-term “traditional” science fiction fandom, such as that associated with Worldcon.
In their own words, “The Fanac, The Fan History Project” is:
devoted to the preservation and distribution of information about science fiction and science fiction fandom. Here you might find your favorite fanzine, pictures of Walt Willis in Ireland or Harlan Ellison at the 1955 Worldcon. You can also find the words to an early filk song, information about an SF con near you AND all sorts of strange and wonderful information about fandom’s past. And the present, too, because that’s tomorrow’s past.
Fancyclopedia begins with:
Science fiction fandom began in the 1930s, when readers of the pulp magazines began to write to each other. While fandom can be a very loose association, its members identify with fandom and with each other, and know many other fans.
Fancyclopedia 3 is a collective enterprise of all of fandom. Based on the previous works by Jack Speer (Fancyclopedia 1), Dick Eney (Fancyclopedia 2), and Rich Brown, it is written by fans who want to contribute.
It continues with:
Like most encyclopedias, Fancyclopedia contains articles on people, events and organizations. It has a Fanzines category. It contains a glossary of fanspeak which is referenced by any articles using fannish terms…
Articles should be relevant to science fiction fandom as such. While comix fandom, animé, and the Society for Creative Anachronism (as examples) arose from science fiction fandom, they are now largely independent. Articles on other fandoms should note their relationships with science fiction fandom and provide links to sites concerned with those fandoms.
Both resources offer a wealth of information to researchers of science fiction and fandom. They are particularly good at providing essential background information on the development of the diversity of contemporary fandoms.